Sains Malaysiana 49(7)(2020): 1509-1520

http://dx.doi.org/10.17576/jsm-2020-4907-04

Estimation of Earth Structure by Satellite Gravity Analysis of Peninsular Malaysia

(Anggaran Struktur Bumi melalui Analisis Graviti Satelit di Semenanjung Malaysia)

NURUL FAIRUZ DIYANA BAHRUDIN^1,2*, UMAR HAMZAH¹ & WAN ZUHAIRI WAN YACCOB¹

¹Geology Programme, School of Environmental Sciences and Natural Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi Selangor Darul Ehsan, Malaysia

²Environmental Tracer Application Group Waste, Technology and Environmental Division, Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor Darul Ehsan, Malaysia

Received: 31 May 2019/Accepted: 8 March 2020

ABSTRACT

Power spectral analysis was successfully carried out on satellite gravity data along 10 East-West profiles of about 140 to 320 km length across Peninsular Malaysia beginning from its border with the Straits of Malacca towards the South China Sea coastline. Power spectrum curves obtained clearly indicate the presence of three major slopes corresponding to four type of materials with different dominant densities. Depth curves computed from all these profiles produced three major dominant peaks beginning with the deepest one at about 33 to 42 km, followed by intermediate depth of 18 to 26 km and the shallowest peaks at about 3 to 10 km. The shallowest depth is interpreted as representing geological formation such as the Mesozoic and Palaeozoic deposits including the granite intrusion classified as basement. Underlying the basement is the upper crustal material extending to Conrad discontinuity at depth of about 18 to 26 km. Earth materials below the Conrad discontinuity constitutes of the lower crustal material overlying the border of upper mantle at depth of 33 to 42 km representing the Mohorovicic discontinuity.

Keywords: Earth structures; satellite gravity data; spectral analysis

ABSTRAK

Analisis kuasa spektrum telah dijalankan ke atas data graviti satelit sepanjang 10 garis rentas timur-barat Semenanjung Malaysia. Panjang garis rentas berjulat antara 140 hingga 320 km. Lengkung kuasa spektrum menunjukkan kehadiran tiga kecerunan utama yang mewakili empat bahan yang mempunyai ketumpatan yang berbeza. Lengkung kedalaman yang diperoleh daripada kecerunan tersebut menghasilkan tiga puncak dominan bermula daripada kedalaman maksimum 33 hingga 42 km diikuti dengan kedalaman sederhana 18 hingga 26 km dan puncak paling cetek pada kedalaman 3 hingga 10 km.  Kedalaman paling cetek ditafsirkan mewakili formasi geologi yang berusia Mesozoik dan Paleozoik termasuk granit yang dikelaskan sebagai besmen. Lapisan besmen ini menindih lapisan kerak atas yang didasari oleh satah ketakselarasan Conrad pada kedalaman 18 hingga 26 km. Bahan bumi di bawah ketakselarasan Conrad terdiri daripada kerak bawah yang menindih sempadan mantel atas pada kedalaman 33 hingga 42 km yang ditafsirkan sebagai satah ketakselarasan Mohorovicic.

Kata kunci: Analisis kuasa spektrum; data graviti satelit; struktur bumi

REFERENCES

Asano, S., Wada, K., Yoshii, Y., Hayakawa, M., Misawa, Y., Moriya, T., Kanazawa, T., Murakami, H., Suzuki, F., Kubota, R. & Suyehiro, K. 1985. Crustal structure in the northern part of the Philippine Sea plate as derived from seismic observations of Hatoyama-off Izu Peninsula explosions. Journal of Physics of the Earth 33(3): 173-189.

Bai, Y., Williams, S.E., Muller, R.D., Liu, Z. & Hosseinpour, M. 2014. Mapping crustal thickness using marine gravity data: Methods and uncertainties. Geophysics 79(2): 27-36.

Bansal. A.R. & Dimri, V.P. 2001. Depth estimation from the scaling power spectral density of nonstationary gravity profile. Pure and Applied Geophysics 158(4): 799-812.

Bhattacharyya, B.K. 1966. Continuous spectrum of the total magnetic anomaly due to a rectangular prismatic body. Geophysics 31(1): 97-121.

Dimitriadis, K., Tselentis, G.A. & Thanassoulas, K. 1987. A basic program for 2-D spectral analysis of gravity data and source-depth estimation. Computers & Geosciences 13(5): 549-560.

Gomez-Ortiz, D. & Agarwal, B.N.P. 2005. 3DINVER.M: A MATLAB program to invert the gravity anomaly over a 3D horizontal density interface by Parker-Oldenburg’s algorithm. Computers & Geosciences 31(4): 513-520.

Iwasaki, T., Levin, V., Nikulin, A. & Idaka, T. 2013. Constraints on the Moho in Japan and Kamchatka. Tectonophysics 609(2013): 184-201.

Kaila, K.L., Tewari, H.C. & Mall, D.M. 1987. Crustal structure and delineation of Gondwana basin in the Mahanadi delta area, India from deep seismic soundings. Journal of the Geological Society of India 29(3): 293-308.

Kieling, K., Roessler, D. & Krueger, F. 2011. Receiver function study in Northern Sumatra and the Malaysian Peninsula. Journal of Seismology 15(2): 235-259.

Kivior, I., Boyd, D., Tucker, D., Markham, S., Vaughan, F., Hagos, F. & Mellon, L. 2013. Deep crustal structures interpreted from potential field data along the deep seismic sounding transect across Olympic Dam, South Australia. ASEG Extended Abstracts 2013(1): 1-4.

Kumar, A., Roy, P.N.S. & Das, L.K. 2016. Vertical density contrast and mapping of basement, Conrad and Moho morphologies through 2D spectral analysis of gravity data in and around Odisha, India. Journal of Asian Earth Sciences 124(2016): 181-190.

Latiff, A.A.H. & Khalil, A.E. 2017. Crustal thickness of North-West Peninsular Malaysia region inferred from receiver function analysis. Seventh International Conference on Geotechnique, Construction Materials and Environment, Mie, Japan. pp. 1-6.

Loke, M.H., Lee, C.Y. & van Klinken, G. 1983. Interpretation of regional gravity and magnetic data in Peninsular Malaysia. Bulletin of the Geological Society of Malaysia 16: 1-22.

Macpherson, K.A., Hidayat, D., Feng, L. & Goh, S.H. 2013. Crustal thickness and velocity structure beneath Singapore's seismic network. Journal of Asian Earth Sciences 64(2013): 245-255.

Maden, N. Gelisli, K., Eyuboglu, Y. & Bekta, O. 2009. Determination of tectonic and crustal structure of the Eastern Pontide orogenic belt (NE Turkey) using gravity and magnetic data. Pure and Applied Geophysics 166(12): 1987-2006.

Mishra, D.C. & Pedersen, L.B. 1982. Statistical analysis of potential fields from subsurface reliefs. Geoexploration 19(4): 247-265.

Mooney, W.D., Laske, G. & Masters, G. 1998. A new global crustal model at 5 × 5 degrees: CRUST5.1. Journal of Geophysical Research 103(B1): 727-747.

Prutkin, I. & Saleh, A. 2009. Gravity and magnetic data inversion for 3D topography of the Moho discontinuity in the Northern Red Sea area, Egypt. Journal of Geodynamics 47(5): 237-245.

Ryall, P.J.C. 1982. Some thoughts on the crustal structure of Peninsular Malaysia - results of a gravity traverse. Bulletin of the Geological Society of Malaysia 15: 9-18.

Singh. A., Singh, C. & Kennett, B.L.N. 2015. A review of crust and upper mantle structure beneath the Indian subcontinent. Tectonophysics 644-645: 1-21.

Spector, A. & Grant, F.S. 1970. Statistical model for the interpreting aeromagnetic data. Geophysics 35(2): 293-302.

Treitel, S., Clement, W.G. & Kaul, R.K. 1971. The spectral determination of depths to buried magnetic basement rocks. Geophysical Journal International 24(4): 415-428.

Zhu, L. & Kanamori, H. 2000. Moho depth variation in Southern California from teleseismic receiver functions. Journal of Geophysical Research: Solid Earth 105(B2): 2969-2980.

*Corresponding author; email: nurulfairuz@nuclearmalaysia.gov.my